I. LITERATURE REVIEW OF OFFSHORE OIL AND GAS DRILLING
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In Egypt, gas production has increased significantly in the Nile delta, where the volumes
extracted quadrupled in 10 years between 1995 and 2005. With the giant gas field called Zohr in
a deep offshore area and the start of production in 2017, the country has become an exporter by
pipeline, notably to Jordan (IFP 2019)
In Tunisia, small offshore deposits have been located in the Gulf of Gabes. Despite a potential
for oil and gas production that remains modest at this stage, exploration remains quite active in
the country's marine waters (IFP 2019).
In Libya, offshore deposits are estimated to be large and promising, especially in the Sirte basin,
which remains under-explored. This explains the great competition from oil companies despite
the unstable situation in the country.
In Algeria, the offshore seismic exploration programme started in spring 2011, in an area
extending offshore between Mostaganem and Annaba. According to recent information, which
was communicated by Sonatrach to several national press media, two exploration drilling
programmes are planned on the east and west coasts. The one on the east coast, offshore between
Skikda and Annaba, will be started after the acquisition of 2D and 3D seismic data in the first
half of 2019. The volume of gas estimated according to the analysis of seismic data is evaluated
at nearly 30 trillion cubic meters, suggesting a similarity between the reserves of this coastline
with the offshore mega deposit of "Zohr" discovered in Egypt (IFP 2019).
The other exploration programme off the west coast is planned between Mostaganem and Oran.
The volumes associated with this first well are estimated at several trillion cubic metres of
biogenic gas. According to these initial investigations, it may also contain oil, with an extraction
estimated at several million barrels. The exploration of the East and West coasts is led by
Sonatrach in partnership with the French Total and the Italian ENI (Algerian-American Energy
Forum).
1.2.3 The regulatory condition for offshore drilling
Oil and gas drilling activities have a high potential to pollute the environment. Drilling fluids are
subject to licensing in many jurisdictions. These are becoming increasingly restrictive as
knowledge of their pollution mechanisms increases. Although minimization of disposal at sea is
required, most countries allow marine discharges of cuttings containing water-based fluid
residues with the requirement that the additives meet toxicity and persistence limits in the
environment (OGP. 2003).
Indeed, in the OSPAR Convention (OSPAR. 1992, 2001), the PLONOR list is the most widely
used classification system for additives. PLONOR substances are considered to present little or
no risk to the environment.
20
In Egypt, gas production has increased significantly in the Nile delta, where the volumes
extracted quadrupled in 10 years between 1995 and 2005. With the giant gas field called Zohr in
a deep offshore area and the start of production in 2017, the country has become an exporter by
pipeline, notably to Jordan (IFP 2019)
In Tunisia, small offshore deposits have been located in the Gulf of Gabes. Despite a potential
for oil and gas production that remains modest at this stage, exploration remains quite active in
the country's marine waters (IFP 2019).
In Libya, offshore deposits are estimated to be large and promising, especially in the Sirte basin,
which remains under-explored. This explains the great competition from oil companies despite
the unstable situation in the country.
In Algeria, the offshore seismic exploration programme started in spring 2011, in an area
extending offshore between Mostaganem and Annaba. According to recent information, which
was communicated by Sonatrach to several national press media, two exploration drilling
programmes are planned on the east and west coasts. The one on the east coast, offshore between
Skikda and Annaba, will be started after the acquisition of 2D and 3D seismic data in the first
half of 2019. The volume of gas estimated according to the analysis of seismic data is evaluated
at nearly 30 trillion cubic meters, suggesting a similarity between the reserves of this coastline
with the offshore mega deposit of "Zohr" discovered in Egypt (IFP 2019).
The other exploration programme off the west coast is planned between Mostaganem and Oran.
The volumes associated with this first well are estimated at several trillion cubic metres of
biogenic gas. According to these initial investigations, it may also contain oil, with an extraction
estimated at several million barrels. The exploration of the East and West coasts is led by
Sonatrach in partnership with the French Total and the Italian ENI (Algerian-American Energy
Forum).
1.2.3 The regulatory condition for offshore drilling
Oil and gas drilling activities have a high potential to pollute the environment. Drilling fluids are
subject to licensing in many jurisdictions. These are becoming increasingly restrictive as
knowledge of their pollution mechanisms increases. Although minimization of disposal at sea is
required, most countries allow marine discharges of cuttings containing water-based fluid
residues with the requirement that the additives meet toxicity and persistence limits in the
environment (OGP. 2003).
Indeed, in the OSPAR Convention (OSPAR. 1992, 2001), the PLONOR list is the most widely
used classification system for additives. PLONOR substances are considered to present little or
no risk to the environment.